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General Category => General Homebrew Discussion => Topic started by: ndcube on January 23, 2010, 10:32:50 PM

Title: Mix-Stir and Head Retention
Post by: ndcube on January 23, 2010, 10:32:50 PM
Just made my first lager.

I decided to aerate after cooling to pitching temp by whipping the crap out of it.  Foam out the sides of the bucket.  The kind of foam I would like to see in my glass.  I couldn't even make it collapse by stirring it into the wort.

Does that form of aeration waste valuable head forming compounds?
Title: Re: Mix-Stir and Head Retention
Post by: dean on January 23, 2010, 11:05:19 PM
Is a de-gassing whip the same thing as the mix-stir?
Title: Re: Mix-Stir and Head Retention
Post by: denny on January 23, 2010, 11:16:39 PM
Yeah, it is dean.

Theoretically, the MixStir action could "use up" foam positive proteins.  However, after using a MixStir for years, I have seen no evidence that's actually happening.  I suppose it's possible that my beers have so much foam potential that losing a little doesn't matter, but at any rate I haven't had anything make me believe it's causing me problems.
Title: Re: Mix-Stir and Head Retention
Post by: ndcube on January 24, 2010, 12:59:26 AM
Yeah, it is dean.

Well, it does the same thing but the design is different.  The degassing whip is just a hook shaped thing where the mixter has the two blades the swing out.

http://www.northernbrewer.com/default/whip-wine-degasser.html
http://www.northernbrewer.com/default/mix-stir-plastic-24.html

I use the whip just because I already have one.
Title: Re: Mix-Stir and Head Retention
Post by: makemehoppy on January 24, 2010, 02:02:16 PM
I agree with Denny (big surprise there). I've been using the mix-stir to aerate for my 3 years of brewing. The owner of my local shop also uses one and has won many awards. I do not think this is a source of any head retention problems you may have.
Have you had any problems or are you just wondering if you may have problems?
Title: Re: Mix-Stir and Head Retention
Post by: ndcube on January 24, 2010, 05:09:35 PM
I agree with Denny (big surprise there). I've been using the mix-stir to aerate for my 3 years of brewing. The owner of my local shop also uses one and has won many awards. I do not think this is a source of any head retention problems you may have.
Have you had any problems or are you just wondering if you may have problems?

I am just wondering.  Usually I have been aerating with O2 and a stone.

I've never had great head retention but I think it's mainly because I have cheap glassware that isn't designated for beer consumption.
Title: Re: Mix-Stir and Head Retention
Post by: denny on January 24, 2010, 05:41:21 PM
I find glassware often has less to do with it than you'd guess.  If you're having "foam issues", take a gander at this.....
http://byo.com/stories/article/indices/35-head-retention/697-getting-good-beer-foam-techniques
Title: Re: Mix-Stir and Head Retention
Post by: ndcube on January 24, 2010, 07:58:47 PM
Thanks Denny.  I'll give it a read.
Title: Re: Mix-Stir and Head Retention
Post by: nyakavt on January 25, 2010, 01:50:31 PM
I've wondered about this myself.  There may be some conditions under which the mix stir could cause head problems: low hop, low protein beer that is mix-stirred and force carbonated with shaking?  I don't know what the limit is, but it seems that the mix stir itself isn't going to give you problems on a regular beer, i.e. there seems to be enough protein to go around.

I have had problems with head retention even without using the mix-stir.  The yeast was healthy, water chemistry good, temp controlled, etc., but still would get a very low-foam beer on almost any style that was not hoppy.  I noticed if these beers were cold conditioned (bottles in the fridge for >4 weeks) that the head formation and retention got a lot better.  Note: this was never a problem with hoppy American style beers, those alpha acids do wonders for foam formation and retention.  I can't make any conclusions from this anecdotal evidence, but it may be something to try if you're having head retention problems.
Title: Re: Mix-Stir and Head Retention
Post by: Kaiser on January 25, 2010, 03:52:33 PM
The effect of foaming during the brewing process and its effect on head retention can be tested in a fairly simple post fermentation experiment.

Needed: 2 carbonated bottles of the same beer, 2l soda bottle, funnel, carbonator cap and CO2

- pour one bottle though the funnel into the empty soda bottle. Make sure it foams a lot but not out of the bottle.
- squeeze out any air and attach carbonator cap.
- add some CO2 and let foam settle
- shake up violently to re-carbonate the beer. Multiple iterations of  decarbonating and carbonating are possible to increase the amount of foaming that the beer went through.
- finally carbonate the beer back to its initial carbonation level and let the foam settle

- take 2 tall glasses, I use Koelsch glasses for that, and with a pour down the center raise a tall foamy head all the way to the rim
- do this for both beers and compare how long it takes until you can see the beer surface.

If there is a big difference there might be something to this but if the times are about the same we should not worry too much.

I perform this head stability test when I evaluate my beers. Usually it takes about 6-7 min for the head to fall back.

Kai